Abstract
Crystalline powders of Si and Co in the composition ratio varying from Si:Co=1:2 to 2:1 were mechanically alloyed by a laboratory ball mill in an inert atmosphere. The amorphization reaction proceeded according to a second-order reaction. The reaction rate decreased with increasing the Co-content. Moreover, crystallization behavior was investigated by differential thermal analysis and the measurement of saturation magnetization. The saturation magnetization of milled Si-Co powders was maximum at 60-80 mol% of Co-content and was larger than that of the corresponding mixture of crystalline powders. Also the saturation magnetization of amorphous Si-Co powders decreased abruptly at a temperature of which the transformation of an amorphous state into a crystalline state began to occur.
